/*
 * printf.c: printf implementation
 *
 * $Id: printf.c,v 1.1 2008/04/14 02:17:49 yuxu Exp $
 *
 *  Copyright (C) 1991, 1992  Linus Torvalds
 *
 * vsprintf.c -- Lars Wirzenius & Linus Torvalds.
 *
 * Wirzenius wrote this portably, Torvalds fucked it up :-)
 *
 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
 * - changed to provide snprintf and vsnprintf functions
 *
 * Taken from linux-2.4.17-rmk3 by Erik Mouw <J.A.K.Mouw@its.tudelft.nl>
 *
 * Note that this code is licensed under GPLv2 only! -- Erik
 *
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ident "$Id: printf.c,v 1.1 2008/04/14 02:17:49 yuxu Exp $"

#include <types.h>
#include <serial.h>
#include <stdarg.h>
#include <util.h>

#undef do_div
#define do_div(n,base)                             \
({                                                 \
 int __res;                                        \
 __res = ((unsigned long)n) % (unsigned int)base;  \
 n = ((unsigned long)n) / (unsigned int)base;      \
 __res;                                            \
})



#define ZEROPAD    1        /* pad with zero */
#define SIGN    2        /* unsigned/signed long */
#define PLUS    4        /* show plus */
#define SPACE    8        /* space if plus */
#define LEFT    16        /* left justified */
#define SPECIAL    32        /* 0x */
#define LARGE    64        /* use 'ABCDEF' instead of 'abcdef' */



static inline int isdigit(char digit)
{
    if (digit >= '0' && digit <= '9' )
        return 1;
    else
        return 0;
}

static inline int strnlen(const char *s, size_t maxlen)
{
    int len;

    len = strlen(s);

    if(len > maxlen)
        return maxlen;
    else
        return len;
}

static int skip_atoi(const char **s)
{
    int i=0;

    while (isdigit(**s))
        i = i*10 + *((*s)++) - '0';
    return i;
}

static char * number(char * buf, char * end, unsigned long long num, int base, int size, int precision, int type)
{
    char c,sign,tmp[66];
    const char *digits;
    const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
    const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    int i;

    digits = (type & LARGE) ? large_digits : small_digits;
    if (type & LEFT)
        type &= ~ZEROPAD;
    if (base < 2 || base > 36)
        return 0;
    c = (type & ZEROPAD) ? '0' : ' ';
    sign = 0;
    if (type & SIGN) {
        if (num < 0) {
            sign = '-';
            num = -num;
            size--;
        } else if (type & PLUS) {
            sign = '+';
            size--;
        } else if (type & SPACE) {
            sign = ' ';
            size--;
        }
    }
    if (type & SPECIAL) {
        if (base == 16)
            size -= 2;
        else if (base == 8)
            size--;
    }
    i = 0;
    if (num == 0)
        tmp[i++]='0';
    else while (num != 0)
        tmp[i++] = digits[do_div(num,base)];
    if (i > precision)
        precision = i;
    size -= precision;
    if (!(type&(ZEROPAD+LEFT))) {
        while(size-->0) {
            if (buf <= end)
                *buf = ' ';
            ++buf;
        }
    }
    if (sign) {
        if (buf <= end)
            *buf = sign;
        ++buf;
    }
    if (type & SPECIAL) {
        if (base==8) {
            if (buf <= end)
                *buf = '0';
            ++buf;
        } else if (base==16) {
            if (buf <= end)
                *buf = '0';
            ++buf;
            if (buf <= end)
                *buf = digits[33];
            ++buf;
        }
    }
    if (!(type & LEFT)) {
        while (size-- > 0) {
            if (buf <= end)
                *buf = c;
            ++buf;
        }
    }
    while (i < precision--) {
        if (buf <= end)
            *buf = '0';
        ++buf;
    }
    while (i-- > 0) {
        if (buf <= end)
            *buf = tmp[i];
        ++buf;
    }
    while (size-- > 0) {
        if (buf <= end)
            *buf = ' ';
        ++buf;
    }
    return buf;
}

/**
* vsnprintf - Format a string and place it in a buffer
* @buf: The buffer to place the result into
* @size: The size of the buffer, including the trailing null space
* @fmt: The format string to use
* @args: Arguments for the format string
*
* Call this function if you are already dealing with a va_list.
* You probably want snprintf instead.
 */
static int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
{
    int len;
    unsigned long long num;
    int i, base;
    char *str, *end, c;
    const char *s;

    int flags;        /* flags to number() */

    int field_width;    /* width of output field */
    int precision;        /* min. # of digits for integers; max
                   number of chars for from string */
    int qualifier;        /* 'h', 'l', or 'L' for integer fields */
                /* 'z' support added 23/7/1999 S.H.    */
                /* 'z' changed to 'Z' --davidm 1/25/99 */

    str = buf;
    end = buf + size - 1;

    if (end < buf - 1) {
        end = ((void *) -1);
        size = end - buf + 1;
    }

    for (; *fmt ; ++fmt) {
        if (*fmt != '%') {
            if (str <= end)
                *str = *fmt;
            ++str;
            continue;
        }

        /* process flags */
        flags = 0;
        repeat:
            ++fmt;        /* this also skips first '%' */
            switch (*fmt) {
                case '-': flags |= LEFT; goto repeat;
                case '+': flags |= PLUS; goto repeat;
                case ' ': flags |= SPACE; goto repeat;
                case '#': flags |= SPECIAL; goto repeat;
                case '0': flags |= ZEROPAD; goto repeat;
            }

        /* get field width */
        field_width = -1;
        if (isdigit(*fmt))
            field_width = skip_atoi(&fmt);
        else if (*fmt == '*') {
            ++fmt;
            /* it's the next argument */
            field_width = va_arg(args, int);
            if (field_width < 0) {
                field_width = -field_width;
                flags |= LEFT;
            }
        }

        /* get the precision */
        precision = -1;
        if (*fmt == '.') {
            ++fmt;
            if (isdigit(*fmt))
                precision = skip_atoi(&fmt);
            else if (*fmt == '*') {
                ++fmt;
                /* it's the next argument */
                precision = va_arg(args, int);
            }
            if (precision < 0)
                precision = 0;
        }

        /* get the conversion qualifier */
        qualifier = -1;
        if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || *fmt =='Z') {
            qualifier = *fmt;
            ++fmt;
            if (qualifier == 'l' && *fmt == 'l') {
                qualifier = 'L';
                ++fmt;
            }
        }

        /* default base */
        base = 10;

        switch (*fmt) {
            case 'c':
                if (!(flags & LEFT)) {
                    while (--field_width > 0) {
                        if (str <= end)
                            *str = ' ';
                        ++str;
                    }
                }
                c = (unsigned char) va_arg(args, int);
                if (str <= end)
                    *str = c;
                ++str;
                while (--field_width > 0) {
                    if (str <= end)
                        *str = ' ';
                    ++str;
                }
                continue;

            case 's':
                s = va_arg(args, char *);
                if (!s)
                    s = "<NULL>";

                len = strnlen(s, precision);

                if (!(flags & LEFT)) {
                    while (len < field_width--) {
                        if (str <= end)
                            *str = ' ';
                        ++str;
                    }
                }
                for (i = 0; i < len; ++i) {
                    if (str <= end)
                        *str = *s;
                    ++str; ++s;
                }
                while (len < field_width--) {
                    if (str <= end)
                        *str = ' ';
                    ++str;
                }
                continue;

            case 'p':
                if (field_width == -1) {
                    field_width = 2*sizeof(void *);
                    flags |= ZEROPAD;
                }
                str = number(str, end,
                        (unsigned long) va_arg(args, void *),
                        16, field_width, precision, flags);
                continue;


            case 'n':
                /* FIXME:
                * What does C99 say about the overflow case here? */
                if (qualifier == 'l') {
                    long * ip = va_arg(args, long *);
                    *ip = (str - buf);
                } else if (qualifier == 'Z') {
                    size_t * ip = va_arg(args, size_t *);
                    *ip = (str - buf);
                } else {
                    int * ip = va_arg(args, int *);
                    *ip = (str - buf);
                }
                continue;

            case '%':
                if (str <= end)
                    *str = '%';
                ++str;
                continue;

                /* integer number formats - set up the flags and "break" */
            case 'o':
                base = 8;
                break;

            case 'X':
                flags |= LARGE;
            case 'x':
                base = 16;
                break;

            case 'd':
            case 'i':
                flags |= SIGN;
            case 'u':
                break;

            default:
                if (str <= end)
                    *str = '%';
                ++str;
                if (*fmt) {
                    if (str <= end)
                        *str = *fmt;
                    ++str;
                } else {
                    --fmt;
                }
                continue;
        }
        if (qualifier == 'L')
            num = va_arg(args, long long);
        else if (qualifier == 'l') {
            num = va_arg(args, unsigned long);
            if (flags & SIGN)
                num = (signed long) num;
        } else if (qualifier == 'Z') {
            num = va_arg(args, size_t);
        } else if (qualifier == 'h') {
            num = (unsigned short) va_arg(args, int);
            if (flags & SIGN)
                num = (signed short) num;
        } else {
            num = va_arg(args, unsigned int);
            if (flags & SIGN)
                num = (signed int) num;
        }
        str = number(str, end, num, base,
                field_width, precision, flags);
    }
    if (str <= end)
        *str = '\0';
    else if (size > 0)
        /* don't write out a null byte if the buf size is zero */
        *end = '\0';
    /* the trailing null byte doesn't count towards the total
    * ++str;
    */
    return str-buf;
}

/**
 * snprintf - Format a string and place it in a buffer
 * @buf: The buffer to place the result into
 * @size: The size of the buffer, including the trailing null space
 * @fmt: The format string to use
 * @...: Arguments for the format string
 */
int snprintf(char * buf, size_t size, const char *fmt, ...)
{
    va_list args;
    int i;

    va_start(args, fmt);
    i=vsnprintf(buf,size,fmt,args);
    va_end(args);
    return i;
}

#define PRINTF_BUFFER_LENGTH 1024
static char printf_buffer[PRINTF_BUFFER_LENGTH];

int printf(const char *fmt, ...)
{
    va_list args;
    int i;

    va_start(args, fmt);
    i = vsnprintf(printf_buffer, PRINTF_BUFFER_LENGTH, fmt, args);
    va_end(args);

    SerialOutputString(printf_buffer);

    return i;
}

int printk(const char *fmt, ...)
{
    va_list args;
    int i;

    va_start(args, fmt);
    i = vsnprintf(printf_buffer, PRINTF_BUFFER_LENGTH, fmt, args);
    va_end(args);

    SerialOutputString(printf_buffer);

    return i;
}

int putchar(int c)
{
    char buffer[2];

    buffer[0] = (char)c;
    buffer[1] = '\0';
    SerialOutputString(buffer);

    return 1;
}

int puts(const char *s)
{
    SerialOutputString(s);
    putchar('\n');
    return strlen(s);
}

void print_buf(char *buf, int num)
{
    int i = 0;
    while (i < num) {
        printf("%08x: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n",
                buf+i,
                *((char *)(buf + i)),
                *((char *)(buf + i + 1)),
                *((char *)(buf + i + 2)),
                *((char *)(buf + i + 3)),
                *((char *)(buf + i + 4)),
                *((char *)(buf + i + 5)),
                *((char *)(buf + i + 6)),
                *((char *)(buf + i + 7)),
                *((char *)(buf + i + 8)),
                *((char *)(buf + i + 9)),
                *((char *)(buf + i + 10)),
                *((char *)(buf + i + 11)),
                *((char *)(buf + i + 12)),
                *((char *)(buf + i + 13)),
                *((char *)(buf + i + 14)),
                *((char *)(buf + i + 15)));
        i += 16;
    }
}
